燃气锅炉燃烧过程中余热回收利用研究

Research on recovery and utilization of waste heat in combustion process of gas boiler

对燃气锅炉燃烧过程的余热进行回收是未来发展的必然趋势。在对天然气基本特征进行介绍的基础上,分析了排烟温度对余热回收中的冷凝率和锅炉供热效率的影响情况,发现存在反比例关系,而空气含湿量对水蒸气露点温度具有促进作用,有利于水蒸气热量的冷凝回收。设计了一种余热回收装置,包含1个间接式换热器和2个直接接触式换热器,对换热器的基本情况进行了介绍。基于EES软件分析了供热负荷为100%、80%、50%和30%时余热回收系统的性能情况,结果发现对应的余热回收量分别为127.6、119.6、92.5、48.1 kJ/s,具有非常好的节能减排效果。

Recovery of waste heat from combustion process of gas boilers is an inevitable trend of future development.On the basis of a brief introduction to the basic characteristics of natural gas,the effect of exhaust gas temperature on condensation rate in waste heat recovery and boiler heating efficiency are analyzed,and it is found that there is an inverse proportional relationship,and the moisture content of the air promotes the water vapor dew point temperature.The effect is conducive to the condensation and recovery of water vapor heat.A waste heat recovery device is designed,including an indirect heat exchanger and two direct contact heat exchangers,and the basic situation of heat exchanger is introduced.Based on EES software,the performance of waste heat recovery system is analyzed when heating load is 100%,80%,50%,and 30%,and it is found that the corresponding waste heat recovery amounts are 127.6,119.6,92.5,and 48.1 kJ/s,respectively.It has a very good effect of energy conservation and emission reduction.